10. Types of diseases
• Infectious disease – Communicated
from diseased person to healthy person.
Caused by some biological agents /
pathogens like – Viruses, bacteria,
protozoan, nematodes, fungi
• Non-infectious disease – Restricted
only to those persons who are suffering.
Diseases that are not caused by
infectious agents.
11. INFECTIOUS DISEASES
• Infectious agents
• Means of spread
• Organ specific & tissue specific
manifestation
• Principles of prevention
12. Infectious agents - Organisms that
can cause disease are found in a
wide range of such categories of
classification.
13. Infectious agent Disease
Virus Common cold, influenza,
dengue fever, AIDS
Bacteria Typhoid fever, cholera,
tuberculosis, anthrax
Fungi Many common
infectious disease
Protozoan Malaria, kala azar
Worms worm infections,
elephantiasis
14. Why is it important
that we think of these
categories
of infectious agents?
15. As an example, let us take
antibiotics.
They commonly block biochemical
pathways important for bacteria. Many
bacteria, For example, make a cell-wall to
protect themselves. The antibiotic
penicillin blocks the bacterial processes
that build the cell wall. As a result, the
growing bacteria become unable to make
cell-walls, and die easily.
16. Means of spread of infectious
disease
1. Air born diseases Common cold,
pneumonia, tuberculosis
2. Water born
diseases
Cholera, amoeboisis
3. Sexually
transmitted
diseases
Syphilis, AIDS
4. Through vectors Anopheles mosquitoes –
vector of malaria
17. Organ specific & tissue specific
Manifestations
After entry of microbes in our body
where do they go?
18. Answer depends on Point of
entry :
• e.g. tuberculosis - caused by bacteria - entry
point through Nose to lungs
19. • e.g. jaundice – caused by viruses – through
mouth to liver
20. To reduce the effects of the disease :-
This can be done by taking medicines to bring down
the effects of the disease like fever, pain or loose
motions etc. and by taking bed rest to conserve our
energy.
To kill the microbes
This can be done by taking suitable antibiotics and
drugs which kills the microbes and the disease is
cured.
Principles of treatment
21. He who has health, has hope;
and he who has hope, has
everything.